Science has found out why we don't like taking risks as we get older

Science has long known that people tend to take fewer risks as they get older. Hence, the phrase: Getting older and wiser.

However, researchers have now found that the cause is in the brain’s changing structure, not simply because we’re ageing or becoming any smarter.

“We know that as people age, they tend to become more averse to taking risks,” says Dr Agnieszka Tymula, from the University of Sydney.

“Yet, it seems there is something to the saying that everybody ages at a different pace. Our research suggests the speed at which our brain’s structure changes has a greater impact on our tolerance of risk than chronological age.”

The research gives insight into the makeup of our community in the future. In about 30 years, adults over the age of 60 are expected to globally outnumber children for the ﬁrst time in history.

“Understanding how such a shift will affect decisions made in our societies on a political and economic level will be hugely important,” says Dr Tymula, who has been studying the factors that influence human decision-making for many years.

“When we choose our life partners, make a bet with a colleague, invest in a stock or vote in presidential elections, we cannot predict with certainty how these decisions will affect us and others. Understanding the brain’s structure can help us predict how our own and others’ decisions will change as our brain ages.”

The research shows risk aversion is better explained by changes in grey matter volume in an area in the brain’s right posterior parietal cortex.

In an experiment, more than 50 adults aged 18 to 88 were asked to make choices between a guaranteed gain of $5 or ambiguous and risky lotteries with a payout of up to $120.

Surprisingly, when researchers put this data into a model to determine what best predicted this change in preference, they found it was primarily driven by the neuronal density — the thickness and thinness of grey matter — in the brain rather than by age.

The research, by Dr Tymula and co-authors from New York University, Yale University, University College London and Trinity College, is published in the journal Nature Communications.